Folding mechanism for a two part endless conveyor

ABSTRACT

A two part endless conveyor ( 10 ) which is adjustable between an in-line operative position, and a folded transport position, and which comprises: a first conveyor part ( 11 ) which is adapted to be mounted at a first end ( 13 ) on the frame of a materiel handling apparatus; a second conveyor part ( 14 ) which is adjustably mounted at a first end ( 15 ) on an opposite second in which the second conveyor part ( 14 ) forms a prolongation of the first conveyor part ( 11 ) and so that the opposite second end ( 17 ) of the second conveyor part ( 14 ) forms a discharge end of the conveyor ( 10 ), and a transport position in which one of the conveyor parts ( 11, 14 ) underlies the other conveyor part and extends generally parallel thereto; and a folding mechanism ( 18 ) which interconnects the second end ( 16 ) of the first conveyor part ( 11 ) to the first end ( 15 ) of the second conveyor part ( 14 ), said mechanism comprising: a coupling block or linkage ( 18 ) which interconnects the second end ( 16 ) of the first conveyor part ( 11 ) and the first end ( 15 ) of the second conveyor part ( 14 ) via a respective one of a pair of pivots ( 20 ); and a pair of linear actuators ( 21 ) each associated with a respective conveyor part ( 11, 14 ) and extending between a mounting point ( 22 ) on the conveyor part and a connection ( 23 ) to the coupling block ( 18 ), each actuator being operative to rotate the coupling block ( 19 ) through approximately  90 ° about the respective pivot ( 20 ), whereby the folding mechanism ( 18 ), under the action of the two linear actuators ( 21 ), can adjust the conveyor parts ( 11, 14 ) between the in-line operative position and the folded transport position.

[0001] This invention relates to a two part endless conveyor which isadjustable between an operative position in which one conveyor partforms a prolongation of the other conveyor part, and a folded transportposition in which the two conveyor parts extend generally parallel to,and are located one above the other.

[0002] Endless conveyor belts have many uses, in order to conveymaterial from one place to another, but a requirement for a foldingfacility is usually only necessary to be provided on apparatus which isintended to be transported from one site to another. Thus, atransportable apparatus has an operative state in which any endlessconveyors provided thereon may project from the apparatus in order todischarge material to deposition zones spaced from the apparatus, butwhich can be folded to transport positions in which the overall lengthand/or height of the apparatus is reduced i.e. the overall “envelope” ofthe apparatus is reduced in size so as to render the apparatus suitablefor being transported from one site to another. Transport may be via alow loader, or via a fifth wheel coupling in the case of a wheeledapparatus.

[0003] The invention has been developed primarily in connection with atwo part endless conveyor which is intended to be mounted on the frameof a transportable material treatment (processing/handling) apparatus,such as a mobile screening and/crushing plant, and which is operativewhen in a deployed mode to discharge treated material to a requireddeposition zone.

[0004] In the case of a screening plant, it is usual to have one or moredischarge conveyor which can be adjusted between an operative positionin which it projects rearwardly, or to one side of the apparatus(usually referred to as a “tail conveyor” or a “side conveyor”respectively), but which can be folded so as to take up a transportposition in which the overall envelope of the apparatus (including thedischarge conveyor(s)) is reduced in size so that the apparatus can betransported along a public highway.

[0005] In the case of a tail conveyor, it is known to design theconveyor in two parts, of which a first part (the head part) ispivotally mounted on the frame of the apparatus so as to be adjustableto an operative position in which any required upward and rearwardinclination of the entire conveyor can be set, so that a stockpile ofmaterial can be formed rearwardly of the apparatus. The tail conveyoralso has a second part (the tail part) which forms a prolongation of thefirst part in the operative position, but can be folded to a transportposition in which one part overlies the other part. In the transportposition, it may be the tail part overlying the head part, or viceversa.

[0006] The head part may also be downwardly adjustable about itspivotable mounting on the frame, in the transport position, in order tofurther reduce the overall height of the conveyor, as well as to reduceits overall length when the two conveyor parts are folded to thetransport position.

[0007] The present invention is primarily concerned with an improvedfolding mechanism which is operative to adjust a two part dischargeconveyor of a mobile material treatment apparatus between a transportposition and a deployed position. However, it should be understood thatthe improved folding mechanism of the invention has general applicationto a two part endless conveyor for use in other suitable apparatus.

[0008] According to the invention there is provided a two part endlessconveyor which is adjustable between an in-line operative position, anda folded transport position, and which comprises:

[0009] a first conveyor part which is adapted to be mounted at a firstend on the frame of a material handling apparatus;

[0010] a second conveyor part which is adjustably mounted at a first endon an opposite second end of the first conveyor part for movementbetween an operative position in which the second conveyor part forms aprolongation of the first conveyor part and so that the opposite secondend of the second conveyor part forms a discharge end of the conveyor,and a transport position in which one of the conveyor parts underliesthe other conveyor part and extends generally parallel thereto; and

[0011] a folding mechanism which interconnects the second end of thefirst conveyor part to the first end of the second conveyor part, saidmechanism comprising:

[0012] a coupling block or linkage which interconnects the second end ofthe first conveyor part and the first end of the second conveyor partvia respective ones of a pair of pivot connections; and

[0013] a pair of linear actuators each associated with a respectiveconveyor part and extending between a mounting point on the conveyorpart and the coupling block, each actuator being operative to rotate thecoupling block through approximately 90° about the respective pivotconnection whereby the folding mechanism, under the action of the twolinear actuators, can adjust the first and second conveyor parts betweenthe in-line operative position and the folded transport position.

[0014] The folding mechanism therefore provides a coupling block whichis relatively rotatable through approximately 90° relative to the secondend of the first conveyor part via a respective pivot connection, andalso is rotatable relatively through approximately 90° about arespective pivot connection to the first end of the second conveyorpart. Therefore, with a relatively simple construction, the two conveyorparts can be readily adjusted between the operative or deployedposition, and the folded transport position, in which the overall lengthof the conveyor is substantially reduced, while at the same time takingup relatively small space, since the conveyor parts are arranged oneabove the other, and generally parallel to each other.

[0015] A two part endless conveyor according to the invention thereforeis particularly suitable for use as a discharge conveyor, and moreparticularly a tail conveyor mounted below a screening plant on a mobilescreening apparatus, in which space is available below the screeningplant which can be occupied by the tail conveyor when folded to itstransport position.

[0016] In a preferred arrangement, the first conveyor part is the headpart of a tail conveyor, and which is adapted to be pivotally mounted onthe frame of the screening apparatus, and can be pivoted about itsmounting point in order to set any required overall inclination of thetail conveyor when in the deployed position, so that the second end ofthe second conveyor part (the tail part) is at a required height so thata stockpile of screened material can be formed at a required locationspaced from the apparatus.

[0017] An endless conveyor has an upper conveyor run and a lowerconveyor run, and it is usual to provide guide or transfer rollers whichfacilitate the movement of the belt along an endless path. Evidently,when the two conveyor parts are folded to the transport position, thishas an effect on the endless belt, and it is therefore preferred that aguide arrangement be provided in the general region of the connectionbetween the two conveyor parts, and which is able to guide the lowerconveyor run, during the folding movement, and also when the foldedtransport position is reached, so as to apply tension to the lowerconveyor run, and thereby at least minimise the risk of slack portionsof the conveyor belt being formed. Conveniently, the guide arrangementcomprises a roller mounted on the coupling block, and which is engagablewith the lower conveyor run, both in the operative position, and in thetransport position, and during adjustment movement of the conveyorparts.

[0018] Any suitable linear actuator may be provided, to interact betweeneach conveyor part and a suitable connection point with the couplingblock, although it will be preferred to use a piston/cylinder device,and preferably a hydraulically operated device.

[0019] The piston cylinder devices may be arranged in a common hydrauliccircuit, in parallel with each other, or may have separate hydrauliccircuits. The devices may operate in sequence i.e. independently of eachother, or simultaneously.

[0020] A preferred embodiment of two part endless conveyor according tothe invention will now be described in detail, by way of example only,with reference to the accompanying drawings, in which:

[0021]FIG. 1 is a side view of a two part endless conveyor according tothe invention, and taking the form of a tail conveyor for mounting onthe frame of a material treatment apparatus, and showing the conveyor ina deployed position in which the head and tail parts of the conveyor arein line with each other i.e. the tail part forms a prolongation of thehead part;

[0022]FIG. 2 is a side view showing the conveyor parts folded to atransport position, in which the head part underlies the tail part, andextends generally parallel thereto;

[0023]FIG. 3 is a detail and enlarged view showing a folding mechanism,interconnecting adjacent ends of the conveyor parts, and in the deployedposition; and

[0024]FIG. 4 is a detail and enlarged view showing the adjustment of thefolding mechanism so as to adjust the conveyor parts to the transportposition.

[0025] Referring first to FIGS. 1 and 2 of the drawings, these are sideviews of the overall length of a two part endless conveyor according tothe invention, designated generally by reference 10, and which may takethe form of a tail conveyor intended to be mounted on the frame (notshown) of a material treatment apparatus, such as a mobile ortransportable screening and/or crushing plant.

[0026] The conveyor 10 has a first conveyor part 11, which is the “headpart”, and which has a pivotable mounting 12 at a first end 13 of theconveyor part 11, by means of which the entire conveyor 10 can bepivotally mounted on the frame of the apparatus. A second conveyor part14, comprising the tail part, is adjustably mounted at a first end 15 onan opposite second end 16 of the first conveyor part 11. The conveyorparts 11 and 14 are relatively adjustable between an in-line operativeor deployed position, as shown in FIG. 1, and a folded transportposition shown in FIG. 2. In the operative position, the second conveyorpart 14 forms a prolongation of the first conveyor part 11, and theopposite second end 17 of the second conveyor part 14 forms thedischarge end of the overall conveyor 10. In the folded transportposition, the second conveyor part 14 underlies the first conveyor part11, and extends generally parallel thereto, so that the folded conveyor10 has reduced overall length, and also takes up a relatively smallspace in the folded position, which is particularly suitable whenmounting the conveyor 10 below a screen box of a mobile screening plant.

[0027]FIGS. 1 and 2 show the overall length of the conveyor 10, andFIGS. 3 and 4 are corresponding illustrations, to an enlarged scale,showing the folding mechanism interconnecting the adjacent ends 15 and16 of the conveyor parts 14 and 11.

[0028] The folding mechanism is designated generally by reference 18,and comprises a coupling block or linkage 19 which interconnects thesecond end 16 of the first conveyor part 11 and the first end 15 of thesecond conveyor part 14 via respective ones of a pair of pivots 20.

[0029] The mechanism 18 also includes a pair of linear actuators 21,each associated with a respective one of the conveyor parts 11, 14, andextending between mounting points 22 on the conveyor parts 11 and 14,and pivot connections 23 to the coupling block 19.

[0030] Each actuator 21, preferably taking the form of a piston cylinderdevice (though other linear actuators may be used) is operative torotate the coupling block 19 through approximately 90° about therespective pivot 20, and therefore a combined relative rotation betweenthe conveyor parts 11 and 14 of approximately 180° can be achieved, formovement between the deployed position, and the transport position.

[0031] Removable locking pins 24 are provided, to maintain the conveyorparts 11 and 14 in the deployed position, and levelling bolts 25 aremounted on the coupling block 19, and engagable with the locking pins24. Adjustment of the levelling bolts 25 permit fine adjustment in therelative inclination between the conveyor parts 11 and 14, when in thedeployed position.

[0032] Referring back to FIGS. 1 and 2, the endless conveyor 10 includesan endless conveyor belt 26 having an upper run 27 and a lower run 28,and guide rollers are mounted on the frames of the conveyor parts 11 and14, to guide the movement of the endless belt 26 on an endless path.Guide rollers 29 are shown guiding the movement of the lower run 28.

[0033] Evidently, when the two conveyor parts 11 and 14 are in thedeployed position, the endless belt 26 is maintained under tension, butupon pivotting of the conveyor part 14 to the transport position thiswill result in release of tension in the lower run 28, and thereforethere may be a tendency for slack portions of belts to form, andespecially in the region of the folding mechanism 18, and this isundesirable. Therefore, at least to minimise this problem, a roller 30is mounted on the coupling block 19, and serves to guide the lower run28 of the endless conveyor belt 26, and seeks to maintain tension in thelower run, (during movement between the operative position and thetransport position), or at least guidance for the endless belt 26 whenin the transport position, thereby avoiding, or at least minimising theformation of slack portion of belt, which might otherwise hangdownwardly from the endless conveyor.

[0034] The illustrated embodiment provides a very satisfactory foldingmechanism between two adjacent ends of a folding conveyor, and withoutgeneration of slack portions of belt falling downwardly under gravityduring movement to the transport position, and it is believed that thistechnical advantage arises directly out of the design parameters of thefolding mechanism. In particular, it will be noted that the pivots 20are located substantially mid height of the respective conveyor partsi.e. approximately midway between the upper and lower belt runs, andthis has a favourable influence on the force which is applied to theendless belt during the folding and unfolding process. The provision ofthe roller 30 also has a favourable influence on the control of tension,and guidance of the lower run of the conveyor belt, during both folding,and unfolding movement. The roller 30, which may be considered to be areturn roller, is located internally on the linkage centre line.

[0035] Also, the means disclosed to permit underfolding, as applied to a“tail conveyor”, provides a length advantage i.e. reduction of about 0.5metres, which is a significant factor in complying with trafficregulations.

1. A two part endless conveyor (10) which is adjustable between anin-line operative position, and a folded transport position, and whichcomprises: a first conveyor part (11) which is adapted to be mounted ata first end (13) on the frame of a material handling apparatus; a secondconveyor part (14) which is adjustably mounted at a first end (15) on anopposite second end (16) of the first conveyor part (11) for movementbetween an operative position in which the second conveyor part (14)forms a prolongation of the first conveyor part (11) and so that theopposite second end (17) of the second conveyor part (14) forms adischarge end of the conveyor (10), and a transport position in whichone of the conveyor parts (11, 14) underlies the other conveyor part andextends generally parallel thereto; and a folding mechanism (18) whichinterconnects the second end (16) of the first conveyor part (11) to thefirst end (15) of the second conveyor part (14), said mechanismcomprising: a coupling block or linkage (18) which interconnects thesecond end (16) of the first conveyor part (11) and the first end (15)of the second conveyor part (14) via a respective one of a pair ofpivots (20); and a pair of linear actuators (21) each associated with arespective conveyor part (11, 14) and extending between a mounting point(22) on the conveyor part and a connection (23) to the coupling block(18), each actuator being operative to rotate the coupling block (19)through approximately 90° about the respective pivot (20), whereby thefolding mechanism (18), under the action of the two linear actuators(21), can adjust the conveyor parts (11, 14) between the in-lineoperative position and the folded transport position.
 2. A conveyoraccording to claim 1 and taking the form of a tail conveyor for mountingon the frame of a material processing apparatus, in which the firstconveyor part (11) is a head part adapted to be mounted on the frame ofthe apparatus, and the second conveyor part (14) is a tail part of theconveyor.
 3. A conveyor according to claim 2, in which the conveyor isadjustable about a mounting part (12) at the first end (13) of the headpart (11), to vary the inclination of the conveyor when in the operativeposition.
 4. A conveyor according to any one of the preceding claims,including a guide arrangement (30) mounted in the folding mechanism (18)and operative to guide the lower run (28) of an endless belt (26)extending along an endless path around the conveyor parts (11, 14), saidguide arrangement being operative to apply tension to the lower run (28)of the endless belt (26) during relative movement of the conveyor parts(11, 14) between the operative position and the transport position. 5.Conveyor according to claim 4, in which the guide arrangement comprisesa roller (30) which is mounted on the coupling block or linkage (19) formovement therewith.
 6. A conveyor according to claim 5, in which theroller (30) is mounted internally on the centre line of the couplingblock or linkage (19).
 7. A conveyor according to anyone of thepreceding claims, in which each linear actuator (21) comprises apiston/cylinder device.
 8. A conveyor according to claim 7, in which thepiston/cylinder devices (21) are hydraulically operable.
 9. A conveyoraccording to claim 8, in which the piston/cylinder devices (21) areoperable independently, or simultaneously.
 10. A material processingapparatus including a conveyor according to any one of claims 1 to 9mounted thereon.